Self Powered Digital Tachometer Hour Meter,Inductive Maintenance Waterproof Backlit Shutdown Tach/Hour Meter,Battery Replaceable,for Lawn Mower Tractor Generator and Gas Engine

What It Is

This is a self-powered digital tachometer and hour meter that uses an inductive pickup to measure engine RPM and run time. It’s designed for lawn mowers, tractors, generators, and any gas engine without a built-in gauge—no wiring to the battery required.

Fitment & Compatibility

• Engine type: Works on any gas engine with a spark plug wire (single or twin cylinder). Not for diesel or battery-only engines.
• Spark plug wire diameter: The inductive sensor wraps around the wire; fits most standard 5-7mm wires. Check your wire’s thickness—if it’s thicker (e.g., 8mm), you may need a larger sensor or shim.
• Mounting: The unit mounts via adhesive pad or zip ties. Ensure a flat, dry surface near the spark plug wire (e.g., on the engine shroud or frame). Avoid mounting near extreme heat sources like the exhaust.
• Battery: Uses a replaceable CR2032 coin cell (included). No hardwiring needed, but the battery compartment is accessible via a small screw—keep a spare.
• Not for: Engines with shielded or resistor-type spark plug wires (e.g., some Kohler or Briggs models)—the inductive pickup may not read reliably. Test by wrapping the sensor and running the engine briefly.

Key Things to Know

• Installation: Easy—wrap the inductive pickup around the spark plug wire (closer to the plug), mount the unit, and start the engine. No tools beyond a screwdriver for the battery door.
• Accuracy: Generally within ±1% for RPM and hours, but may need a “pulse-per-revolution” setting for twin-cylinder engines (default is 1 pulse/rev). Check your engine’s firing order.
• Waterproofing: Rated IP65, but the battery compartment and sensor connection are weak points. Use dielectric grease on the battery contacts and seal the sensor wire entry with silicone if exposed to heavy rain or pressure washing.
• Display: Backlit LCD with auto-shutdown after 30 seconds of no engine activity to save battery. Hour meter resets only with a new battery—no manual reset.

Should You Buy It

Buy if you need a simple, no-wire way to track engine hours and RPM for maintenance scheduling (oil changes, blade sharpening) on a gas-powered mower, generator, or tractor. Skip if your engine has a shielded spark plug wire or you want a hardwired unit with a permanent power source.